Can not run fastify cli in watch mode with node inspector

[pyxarez]

🐛 Bug Report

Cli is not working in --watch mode with node inspect on the board
It throws the following log: Starting inspector on 127.0.0.1:9230 failed: address already in use

To Reproduce

Steps to reproduce the behavior:

Paste your code here:

node --inspect-brk=9230 ./node_modules/.bin/fastify start --watch -l info -P app.js

Expected behavior

It should work in --watch mode with node inspect on the board

Your Environment

• node version: 10
• fastify version: >=2.0.0
• os: Mac

[mcollina]

This happens because we are forking the project: https://github.com/fastify/fastify-cli/blob/master/lib/watch/fork.js. We might want to do something about this, as it's a rather convenient feature.

Can you do the same with Nodemon for example? How do they implement/support it?

[pyxarez]

Can you do the same with Nodemon for example? How do they implement/support it?

I don't fully understand the question
Yea, I can try to do the same with nodemon, but it requires migrating from cli, making my own server.js and leads to loss of fastify-cli functionality like logging, default setup, etc.
It will look like this nodemon --inspect=9230 server.js

[mcollina]

You answered the question! nodemon implements it via a --inspect flag. Would you like to send a PR that adds that to fastify-cli as well?

[pyxarez]

Hmm, that's an interesting idea
Yeah, I can try to do that, but I'm new in fastify and I think it'll take some time
If you do not need super fast fix that's the task for me

[mcollina]

Go ahead!

[xtx1130]

I am sure child_process.fork() caused this, you need add options {execArgv: []} to cp.fork()

[pyxarez]

@xtx1130 , I tried you suggestion and it's actually work!
But will this not lead to errors in the case when we really want to use execArgv?

[pyxarez]

I admit that that's an internal usage of fork and there is no case when someone would like to parametrise that part from outisde

[gbertoncelli]

I'm going to make a PR of this if you want... I was able to manage that with execArgv parameter and adding a debug flag to the CLI.

I'm trying now to use the debug flag also without watch mode, but I'm working on that...

[pyxarez]

@HighSoftWare96 yay! Great news:)
I don't have enough time for it anyway:)
Thank you

[xtx1130]

@pyxarez

But will this not lead to errors in the case when we really want to use execArgv?

I think it's better to move execArgv to fork's args.

[gbertoncelli]

I think this issue can be closed, don't you @pyxarez ? The initial behaviour can be solved now by using:
fastify start --watch -l info -P app.js -d --debug-port=9230

[pyxarez]

Yeah, sure
Thank you all for your help!

[almgwary]

Anyone know how to start fustily start on debugging mode? all above solutions not working with me. debug server is started but not attached to the running server.